The World Health Organisation this weekend rejected calls from 150 of the world's leading scientists to reschedule the Olympics because of the ongoing threat from the virus.

The majority of those infected with Zika will have no symptoms, but for others it can cause a mild illness with symptoms including a rash, fever and headache.

Serious complications that arise from infection are not common but experts have said the virus can cause microcephaly, where babies are born with abnormally small heads due to the fact their brains have not developed properly.

As the temperature rises in some parts of the world in the next few months, scientists have warned those most at risk to consider their travel plans.

Professor Jimmy Whitworth, from the London School of Hygiene and Tropical Medicine, said while he does not consider there to be a risk from travelling to Disney World in Florida now, there could be later in the summer.

He told the Mail on Sunday women who are pregnant or hoping to get pregnant "need to consider their plans and, if there is an alternative to going to those parts of the US, strongly consider it".

As for the risk posed by those travelling to the Olympic Games, Professor Jeremy Farrar, director of the Wellcome Trust, said it is insufficient to cause a major impact on the overall spread of the virus.

He told the Observer: "The numbers travelling to and from Brazil for the Games is likely to account for about 0.25% of world travel.

"That does not pose a sufficient risk of spreading the disease in my view.

"Mosquitoes in August are not nearly so active in Brazil as at other times of the year. Risks are therefore reduced."

His comments echo those already expressed by Jonathan Ball, Professor of Molecular Virology at the University of Nottingham, who said while people need to be careful when travelling, the risk from Olympic travel alone is "a drop in the ocean" compared with routine trips and trade.